解放日以来美国贸易的演变

US trade policy has entered a new, unstable regime. One year after Liberation Day,tariffs remain far higher than pre-2025 levels, despite a Supreme Court ruling thatoverturned much of the original framework. A temporary universal tariff has simplified Higher tariffs have reshaped trade patterns, not reduced the trade deficit. The US tradedeficit remains wide as strong domestic demand, front-loading effects and higher Trade diversion has dominated the adjustment. Imports from China have fallen sharply,but this has been offset by rising shipments from other Asian economies and Mexico, as Capital goods andhigh-techimports have proven remarkably resilient. AIrelatedinvestment has sustained demand for machinery, electronics and semiconductors, Tariffs are now embedded in the system, with further reconfiguration ahead. Withexemptions expanding, legal risks unresolved and new investigations underway, future Trade policy in flux Phase 1 January-March 2025: extending trade war 1.0The administration initially extended the tariff framework from Trump’s first term. A 10% tariff on China announced on 4February effectively reactivated the US–China trade war, whileCanada and Mexico wereroped in as well with tariffs motivated At the start of 2025, the United States maintained one of themost open trade regimes among major economies. Theeffective tariff rate, measured as tariff revenue relative to totalimports, stood between 2% and 3%, broadly inline with theprevailing levelsince the liberalisation of global tradeinthe Phase 2 April 2025: Liberation Day and systemic escalationOn 2 April 2025, “Liberation Day”, the US announced the largest In this research note, wepresent an overviewof how the US hasused tariffsas a policy toolsincethe start of President Trump’ssecondadministration, setting the stage for the current tarifflandscape and outlook.While there are manypurported aims forthese tariffs, one of the most fundamental–underpinning theUS-China trade war started in 2018–is the rebalancing of trade tariff increase in modern history. Emergency powers undertheInternational Emergency EconomicPowers Act (IEEPA)wereused to introduce a universal 10% tariff and reciprocal rates ofup to 50% on selected surplus countries, alongside new Phase 3 May-August 2025: tariff diplomacyMarket pressure led to a partial retreat. Reciprocal tariffs above 10% were paused for most countries, while the USnegotiateddeals withthe EU, UK, Japan and India.The US and China alsoreached a truce in May.Countries without agreements faced Tariff evolutionin trade war2.0 Since January 2025, US tariff policy has moved through fivedistinct phases, reflecting shifts in strategy and economicimpact(figure 1). Statutory tariffs refer to the rates announcedin trade policy decisions. The measured effective tariff rate bycontrast reflects the tariffs actually paid across all imports, Phase 4Late 2025-early 2026: stabilisation and adjustment Following the intense negotiation phase, US trade policyentered a period of relativestability.The administration continued tousetariffs, or the threats thereof,for politicalleveragebut the effectivetariffratestayedrelatively flat.Duringthis phase, the administration increasingly relied on targetedexemptions for sensitive industries like computersas well as Figure2Country-level effective tariff rates Phase 5Late February-March2026: legal disruption and policyreset A Supreme Court ruling in the end of February 2026invalidatedmost emergency-based tariffs–amounting toabout 75% of allUS tariffs.Theadministrationresponded by introducingatemporary universal tariff under Section 122 of the1974TradeAct, replacing the previous country-specific tariff regime with a The current tarifflandscape TheUS’scomplicated post-Liberation-Daytariff regimeofcountry-specific tariffshas been replaced by a relatively simpler Countries that faced the highest tariffs under the reciprocaltariff system have seen the largest reductions in tariff exposure.Brazil’s effective tariff rate fell from 29.3% to 11.4% while China’sdecreasedfrom 29.2% to 19.2%.Other AsiancountrieslikeBangladesh,Indonesiaand Vietnamwere also the main ▪a universal 10%tariff on all imports under Section 122, and▪pre-existing sectoral tariffsincluding those on steel (50%), aluminium (50%), copper (50%) and autos (25%) The 10% blanket rate entered into effect on 24 February andstacks on top of existing most-favoured-nation (MFN) tariffsand earlier trade-war measures like Section 301 tariffs onChinese goods.It also still includesexemptions for USMCA-compliant goods from Canada and Mexicoandtextiles from DR- For many countries, especially US allies, the transition to Section122 has had limited effect.Canada and Mexico have seen verylittle change in the duties for their US exports since the USMCAexemption was maintained. EU countries like Germany andFrance have seen minor reductions while the UK’s tariff ratehardly budged.This is because they had already negotiated A m